The invention relates to GDF promoters, such as GDF-8 promoters, as well as methods of using them, e.g., methods for screening for regulatory compounds of GDF-8 expression.
GDF-8 is a member of the TGF-xcex2 superfamily, which encompasses a large group of growth and differentiation factors that play important roles in regulating embryonic development and in maintaining tissue homeostasis in adult mammals. GDF-8 appears to function specifically as a negative regulator of skeletal muscle growth and, therefore, has potential applications in producing livestock and game animals, such as cows, sheep, pigs, chicken, turkey, and fish which are relatively high in musculature and protein, and low in fat content. In addition, GDF-8 has potential applications in various cell proliferative and differentiation disorders, especially those involving muscle, nerve and adipose tissues in both human and animals. GDF-8 also appears to be involved in glucose transport and, therefore, has potential applications in the treatment or diagnosis of glucose transport associated disorders such as diabetes.
Many drug and diet regimens exist which may help increase muscle and protein content and lower undesirably high fat and/or cholesterol levels, but such treatment is generally administered after the fact, and is begun only after significant damage has occurred to the vasculature. Accordingly, it would be desirable to produce animals which are genetically predisposed to having higher muscle content, without any ancillary increase in fat levels. U.S. patent application Ser. No. 09/019,070, inventors Se-Jin Lee and Alexandra C. McPherron, filed Feb. 5, 1998 and entitled Growth Differentiation Factor-8 also describes the production of GDF-8, as well as potential uses. This application is also hereby incorporated by reference.
Control of GDF-8 gene expression is highly desirable. The availability of discreet DNA segments which are capable of conferring either a negative or positive control capability to known genes in eukaryotic systems is generally lacking in the art. Isolation of regulatory genetic sequences for GDF-8 is disclosed in the present invention.
The present invention relates to the molecular regulation of GDF-8 expression and, in particular, to the isolation and identification of regulatory sequences of GDF gene promoters, such as the GDF-8 gene promoter.
In one embodiment, the present invention provides the complete nucleotide sequence and identification of genetic regulatory elements which promote expression of GDF-8.
In another embodiment, the present invention provides a method of screening for compounds which regulate GDF-8 expression, for example, by inhibiting or by stimulating GDF-8 expression.
In yet another embodiment, the present invention provides a DNA expression construct containing the GDF-8 promoter operatively linked to a gene of interest (GOI), and a method of expressing a GOI in muscle and other tissues (e.g., tissues in which GDF-8 is naturally expressed).